UV-C LED disinfection efficacy proven to combat viruses

NICHIA’s UV-C LED technology was extensively tested at Tokushima University to demonstrate its bacteria and virus disinfection efficiencies. Experiments conducted by the university’s Biomedical Sciences department confirmed that irradiating SARS-CoV-2 with NICHIA’S NCSU334B for 30 seconds, with 51mJ/cm2, exhibited 99.99% inactivation (as can be seen in Figure 1 below), a key activation log to achieve.

Additionally, the experiment was operated based of the NCSU334B’s binned input power and conditions of 1.7mJ/cm2 and five centimetre distance. There remains adequate room to reduce the time or increase the dosage depending on the conditions or the design of its working distance, the number of LEDs or the input power. For example, when designing with half the working distance, the performance increases four times.

NICHIA has scaled up its investment in R&D and manufacturing capacity for its UV LED solutions. Now in mass production, NICHIA’s NCSU334B at 280 nm achieves high output, efficiency and lifetime. It delivers a typical irradiance of 70mW with a wall-plug efficiency (also known as radiance efficiency) of 3.6%, an improvement of 27% compared to its predecessor. With a hermetic seal, the solution also provides long lifetime performance, especially at peak temperatures and humidity levels.

While traditional UV-C technologies, such as low-pressure mercury vapor lamps, are limited to a 254nm peak, the most efficient wavelength to disinfect bacteria and viruses is known to be 260nm due to the peak absorption spectrum of the DNA/RNA. However, NICHIA has demonstrated that 280nm delivers the highest virucidal power as it has a very strong irradiance, wall-plug efficiency and lifetime, all at practical operating conditions.

Indeed, data highlights have reportedly shown that the virucidal power of the 280nm LED is approximately 1.3 times (127%) that of 265nm LEDs. The 280 nm LED also delivers a lifetime ten times longer than a 265nm LED.

Generally, the advantageous compact size of LED-based UV-C solutions means that they can be directly integrated within disinfection applications in restricted spaces including industrial applications, water purifiers, air conditioning systems and more.

UV-C light is making a significant contribution to combatting viruses and bacteria, simplifying traditional methods. For example, to obtain a high viricidal effect (i.e. four-log) when using an alcohol solution for disinfection (containing 77 to 81% ethanol), surfaces need to be sufficiently wetted with the substance or require significant effort and time, often times beyond 30 seconds. Used in conjunction with such measures, NICHIA’s 280nm deep UV LED can offer a high viricidal effect while saving time and effort.